FIGS. 1 and 2 show a conventional protecting device of the lead-out line 11a of a plug 10a. The lead-out line 11a of the plug 10a is electrically connected to a conductive wire 12a. To prevent the over-bending on the junction of the lead-out line 11a of the plug 10a and the conductive wire 12a, a protecting device composed of circular ribbons 14a and axial ribbons 15a are provided on the outer surface of the cladding over the part of the conductive wire 12a in connection with the lead-out line 11a of the plug 10a. As shown in FIG. 2, the circular ribbons 14a and axial ribbons 15a can prevent over-bending of the junction between the lead-out line 11a of the plug 10a and the conductive wire 12a, when the lead-out line 1 a is bent with respect to the conductive wire 12a.
However, as shown in FIG. 2, a sharp curve is easy to form on portion 16a of the conductive wire 12a adjoining to the protecting device when the conductive wire 12a is pulled out. The copper coil of the conductive wire 12a in the portion 16a is liable to break due to the sharp curve, thus reducing the endurance of the conductive wire 12a and the plug 10a.
It is the primary object of the present invention to provide a protecting device for the lead-out line of various plugs, whereby the accuracy of test and the durability of the plug are enhanced.
To achieve the above object, the present invention provides a spiral ribbon as protecting means around the cladding on the junction of the lead-out line and the conductive wire, the spiral ribbon keeping the smooth bending of the conductive wire and preventing the breakage of the upper coil within the conductive wire. the spiral ribbon can prevent the forming of sharp bending between the lead-out line of the plug and the conductive wire when the conductive wire is pulled out. Therefore, the accuracy of test and the endurance of the plug are enhanced.
The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawing, in which: